Quote:
Originally Posted by iceman
Hi Trev.
The second one does look much better in terms of contrast and highlighting the detail.
I pretty much use the 5x ALL the time now. Sometimes the conditions just aren't good enough for it, but so be it. It might just mean I go back inside and try again another night. The 5x gives me a focal length of about 10m.
What's the focal length of your 16"?
Do you have any active or passive cooling for the primary mirror?
I think you should definitely persist with the 3x - but having said that, if your aim is to get a pleasing image and the conditions aren't that great, then dropping back to a 2x will give you that opportunity.
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Hi Mike,
The focal length of my scope is 1829mm and I have an active cooling system on my primary (see attached image). I usually turn it on about an hour before I am planing to image.
This has been my first experience imaging at 3x, as you have mentioned in a previous post the effective spacing provided by the filter wheel probably provided extra magnification.
I see great possibilities in persevering with the 3x but the quality of the seeing will be a major consideration. I have read through your articles on processing and found them most helpful. Most of the post processing that you suggest can be done in AstraImage Pro. I am still coming to grips with this software and have experimented with most of the functions within it.
The seeing out here in Broken Hill is generally very good so I think I just need to persist and hopefully improve my technique.
I put a lot of effort into the collimation of my scope, with the scope set up in the position it will be in when I am imaging. I have the complete Tectron collimating kit and swear by the Cheshire and a very nice double pass laser. I regularly test the laser in my lathe. I set it up in a three jaw self centering chuck and have the laser aligned on a target 15 ft away through the headstock of the lathe.
Nothing is perfect in this world but the alignment of my laser is always bloody close.
Regards
Trev